GROWING HARDY CYCLAMEN FROM SEED

A little effort will yield a magic carpet of these choice perennials

by ELLEN HORNIG

HOW MANY OF US DREAM of drifts of cyclamen illuminating the fall garden, or adorning the drab landscape of earliest spring, only to find that the numbers required to produce the desired effect cost more than the gardening budget can bear? Yes, large numbers of small plants surely do add up. Planted on eight-inch centers, Cyclamen hederifolium (fall-blooming) or C. coum (spring-blooming) compete with high-quality carpeting. At $4 to $6 per plant, those flower carpets will run you between $104 and $156 per square yard. That 30-foot swath is going to be pricey, indeed.

And yet cyclamen are not that difficult to grow from seed. With fresh seed, a cool growing space (around 60°F is optimal), and a reasonable amount of patience, you can produce your own drifts for pennies on the dollar.

First, the seed. Fresh seed of C. hederifolium and C. coum can often be obtained directly from cyclamen specialists. Expect to pay $.10 to $.30 per seed; these little tidbits have to be patiently gathered and cleaned over a staggered ripening period of several weeks. The seeds of both species ripen in July, despite their different blooming times. For optimal results, you want to sow them within six weeks of ripening. If freshly harvested seed is unavailable, though, don’t spurn older seeds—you may still get very good germination, though it will be slower and more erratic than with fresh seed. Just soak the seeds before sowing: 24 hours in plain water should do the trick. Fresh seeds do not need soaking.

To sow and grow your cyclamen, you’ll need the following (photo 1):

3.5-inch plastic pots (figure on 20–25 seeds per pot)

10-inch-by-20-inch nursery flats for the pots (3.5-inch pots fit 18 to a flat)

a clear plastic dome for each tray

pot labels and pencils

fresh seed or presoaked older seed

seed germinating mix*

chick starter grit**

a cool growing space

fluorescent lighting (basic, inexpensive cool-white tubes are fine)

*I use Fafard Superfine Germinating mix, but any standard peat/perlite/vermiculite mix should work.

**Sold as Grani-Grit, starter size; available at farm and feed stores. This is a crushed-granite product; do not use a grit amended with crushed shells. Turface can be substituted.

After placing the pots in the nursery flat, water each one thoroughly and allow to drain.

To sow the seeds, place 20 to 25 seeds on the surface of each filled pot (photo 2). Take the time to place them at even intervals, so each will have its fair share of growing space as it matures. When all have been placed, water lightly from the top to settle the seeds into the surface. Cover the seeds with 3/8 inch of pure starter grit (photo 3). When all have been sown, give them a final light watering to settle them in (photo 4), cover the flat with a clear plastic dome, and leave it where it can continue to drain for several hours. (This is important; a soggy medium will lead to rot.)

Because cyclamen seeds germinate best at cool temperatures and in the dark, you’ll need to handle them rather differently from other seeds. Place your sowed seed flats in a cool room (as close to 60°F as you can manage, but anything between 50°F and 68°F will do) and cover with a few layers of newspaper. (It isn’t necessary to exclude every photon.) Then wait. Cyclamen hederifolium needs a minimum of two weeks to germinate; C. coum closer to four weeks. If the seeds are not fresh, or the room is colder than 60°F, it will probably take longer—possibly several weeks longer. Do not attempt to hurry germination by raising the temperature—it won’t work! Cyclamen, like other plants with a Mediterranean growth cycle (summer-dormant, winter-active), are adapted to germinating as average temperatures fall at the end of summer and into autumn. Heat them up, and you’ll send them exactly the wrong signal.

After the requisite waiting period, you’ll notice the surface of the grit on the pots starting to heave. This signals the development of tiny tubers directly from the seed. Now is the time to remove the plastic dome and set the pots under fluorescent lights. (The lights should be roughly four inches above the pot surface.) Give the pots a thorough watering at this time, too, and as always, let them drain thoroughly before returning them to a flat surface. Once the little tubers have formed, each will send up its first leaf. Don’t be disappointed if these leaves look rather plain; you can’t really tell how well-colored or marked the leaves will be until the tubers are more mature.

From this point on, your goal is to keep the cyclamen in leaf as long as possible, so that they can build up their tubers as fast as possible and reach transplantable and blooming size. To this end, keep them under lights for at least 14 hours a day, at between 50°F and 68°F (but near 60°F is still best). You’ll find that leaves keep emerging over an extended period (several weeks). When you’re pretty sure most have fully unfurled, start fertilizing your babies, adding a balanced water-soluble fertilizer with micronutrients at one-quarter strength to every other watering. Pay close attention to watering, as it’s important that the pots get neither soggy nor dry. If you must err either way, let them get too dry. Keep them too wet, and they will surely rot. Ensure good air circulation in your growing area with a small fan set on low speed and kept at least 10 feet from the seedling flats.

As spring progresses and ambient temperatures rise, your seedlings will cease new growth. (Remember that they’re programmed to go dormant in the summer heat.) If you can keep temperatures on the cool side, you may be able to keep them in leaf, though not in active growth, through their first summer. If this is the case, water sparingly—just enough to keep the leaves turgid. If you can’t keep them cool, you must allow them to go dormant. You’ll know they’re ready because their leaves will look increasingly “tired,” and start to fade and yellow. Withhold most water and all fertilizer, keeping the medium just barely damp. Cyclamen have perennial roots, and you don’t want these to die. As when they’re in active growth, you’ll do far less damage by allowing them to get too dry than you will by overwatering.

Depending on how large your tubers have grown in their first year, you may be able to plant them out in the garden roughly one year after sowing. The time to do this is when growth resumes in late summer or early fall. (You’ll see fresh little growth points appearing on the tops of the tubers.) There is no firm size rule, but in general, a tuber should be at least one-half inch across, and have a large, well-branched root system (photos 5 and 6). The tubers should be planted just under the soil surface (though they can be planted much deeper, if the leaves haven’t developed yet) and covered with a light mulch that will not compact. If you have large numbers and are not inclined to coddle every one, you can plant even the small ones. Here at the nursery, we always find that the tiny extras we’re too lazy to deal with do surprisingly well when we toss them into a well-mulched garden, water them into the mulch, and forget about them.

If you do want to coddle them, plant out only the well-developed tubers, and replant the others in community or individual pots (photo 7). They’ll do best if you group them in deep flats or pots, in a well-drained compost. A light surface mulch of grower grit (the next size up from the chick grit you used in your starter mix) will help keep the medium evenly moist. Grow them on for another year, and all should be ready for the garden.

And then, if all goes well, and the rodents don’t get too hungry, your cyclamen “carpet” will start to form. Happy cyclamen will self-sow, and you’ll be able to prick out extras and move them elsewhere in the garden. New leaf forms and flower colors will appear, and you’ll be amply rewarded for your months of patient, loving care. H